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filename src/gdrom/gdrom.c
changeset 237:6f1a429c9d12
prev168:203a72138e16
next245:a1d0655a88d3
author nkeynes
date Tue Dec 19 09:51:35 2006 +0000 (17 years ago)
permissions -rw-r--r--
last change First cut of port 576890 (sysreset) and ide enable/disable
view annotate diff log raw 
     1 /**

     2  * $Id: gdrom.c,v 1.10 2006-12-14 12:31:38 nkeynes Exp $

     3  *

     4  * GD-Rom  access functions.

     5  *

     6  * Copyright (c) 2005 Nathan Keynes.

     7  *

     8  * This program is free software; you can redistribute it and/or modify

     9  * it under the terms of the GNU General Public License as published by

    10  * the Free Software Foundation; either version 2 of the License, or

    11  * (at your option) any later version.

    12  *

    13  * This program is distributed in the hope that it will be useful,

    14  * but WITHOUT ANY WARRANTY; without even the implied warranty of

    15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    16  * GNU General Public License for more details.

    17  */

    18 

    19 #include <stdio.h>

    20 #include <fcntl.h>

    21 #include <errno.h>

    22 #include "gdrom/ide.h"

    23 #include "gdrom/gdrom.h"

    24 #include "gdrom/packet.h"

    25 #include "dream.h"

    26 

    27 static void gdrom_image_destroy( gdrom_disc_t );

    28 static gdrom_error_t gdrom_image_read_sectors( gdrom_disc_t, uint32_t, uint32_t, int, char *, uint32_t * );

    29 

    30 gdrom_image_class_t gdrom_image_classes[] = { &linux_device_class, &nrg_image_class, &cdi_image_class, NULL };

    31 

    32 gdrom_disc_t gdrom_disc = NULL;

    33 

    34 char *gdrom_mode_names[] = { "Mode1", "Mode2", "XA 1", "XA2", "Audio", "GD-Rom" };

    35 uint32_t gdrom_sector_size[] = { 2048, 2336, 2048, 2324, 2352, 2336 };

    36 

    37 gdrom_disc_t gdrom_image_open( const gchar *filename )

    38 {

    39     const gchar *ext = strrchr(filename, '.');

    40     gdrom_disc_t disc = NULL;

    41 

    42     int fd = open( filename, O_RDONLY | O_NONBLOCK );

    43     FILE *f;

    44     int i,j;

    45     gdrom_image_class_t extclz = NULL;

    46 

    47     if( fd == -1 ) {

    48 	ERROR("Unable to open file '%s': %s", filename, strerror(errno));

    49 	return NULL;

    50     }

    51 

    52     f = fdopen(fd, "ro");

    53 

    54 

    55     /* try extensions */

    56     if( ext != NULL ) {

    57 	ext++; /* Skip the '.' */

    58 	for( i=0; gdrom_image_classes[i] != NULL; i++ ) {

    59 	    if( gdrom_image_classes[i]->extension != NULL &&

    60 		strcasecmp( gdrom_image_classes[i]->extension, ext ) == 0 ) {

    61 		extclz = gdrom_image_classes[i];

    62 		if( extclz->is_valid_file(f) ) {

    63 		    disc = extclz->open_image_file(filename, f);

    64 		    if( disc != NULL )

    65 			return disc;

    66 		}

    67 		break;

    68 	    }

    69 	}

    70     }

    71 

    72     /* Okay, fall back to magic */

    73     gboolean recognized = FALSE;

    74     for( i=0; gdrom_image_classes[i] != NULL; i++ ) {

    75 	if( gdrom_image_classes[i] != extclz &&

    76 	    gdrom_image_classes[i]->is_valid_file(f) ) {

    77 	    recognized = TRUE;

    78 	    disc = gdrom_image_classes[i]->open_image_file(filename, f);

    79 	    if( disc != NULL )

    80 		return disc;

    81 	}

    82     }

    83 

    84     if( !recognized ) {

    85 	ERROR( "Unable to open disc %s: Unsupported format", filename );

    86     }

    87     fclose(f);

    88     return NULL;

    89 }

    90 

    91 

    92 gdrom_disc_t gdrom_image_new( FILE *file )

    93 {

    94     struct gdrom_disc *disc = (struct gdrom_disc *)calloc(1, sizeof(struct gdrom_disc));

    95     if( disc == NULL )

    96 	return NULL;

    97     disc->read_sectors = gdrom_image_read_sectors;

    98     disc->close = gdrom_image_destroy;

    99     disc->disc_type = IDE_DISC_CDROM;

   100     disc->file = file;

   101     return disc;

   102 }

   103 

   104 static void gdrom_image_destroy( gdrom_disc_t disc )

   105 {

   106     if( disc->file != NULL ) {

   107 	fclose(disc->file);

   108 	disc->file = NULL;

   109     }

   110     free( disc );

   111 }

   112 

   113 static gdrom_error_t gdrom_image_read_sectors( gdrom_disc_t disc, uint32_t sector,

   114 					       uint32_t sector_count, int mode, char *buf,

   115 					       uint32_t *length )

   116 {

   117     int i, file_offset, read_len;

   118     struct gdrom_track *track = NULL;

   119 

   120     for( i=0; i<disc->track_count; i++ ) {

   121 	if( disc->track[i].lba <= sector && 

   122 	    (sector + sector_count) <= (disc->track[i].lba + disc->track[i].sector_count) ) {

   123 	    track = &disc->track[i];

   124 	    break;

   125 	}

   126     }

   127     if( track == NULL )

   128 	return PKT_ERR_BADREAD;

   129 

   130     file_offset = track->offset + track->sector_size * (sector - track->lba);

   131     read_len = track->sector_size * sector_count;

   132 

   133     switch( mode ) {

   134     case GDROM_GD:

   135 	// Temporarily comment this out - it's wrong, but...

   136 	//	if( track->mode != GDROM_GD ) 

   137 	//    return PKT_ERR_BADREADMODE;

   138 	// break;

   139     case GDROM_MODE1:

   140 	switch( track->mode ) {

   141 	case GDROM_MODE1:

   142 	case GDROM_MODE2_XA1:

   143 	    fseek( disc->file, file_offset, SEEK_SET );

   144 	    fread( buf, track->sector_size, sector_count, disc->file );

   145 	    break;

   146 	case GDROM_MODE2:

   147 	    read_len = sector_count * 2048;

   148 	    file_offset += 8; /* skip the subheader */

   149 	    while( sector_count > 0 ) {

   150 		fseek( disc->file, file_offset, SEEK_SET );

   151 		fread( buf, 2048, 1, disc->file );

   152 		file_offset += track->sector_size;

   153 		buf += 2048;

   154 		sector_count--;

   155 	    }

   156 	    break;

   157 	default:

   158 	    return PKT_ERR_BADREADMODE;

   159 	}

   160 	break;

   161     default:

   162 	return PKT_ERR_BADREADMODE;

   163     }

   164 	    

   165     *length = read_len;

   166     return PKT_ERR_OK;

   167 }

   168 

   169 uint32_t gdrom_read_sectors( uint32_t sector, uint32_t sector_count,

   170 			     int mode, char *buf, uint32_t *length )

   171 {

   172     if( gdrom_disc == NULL )

   173 	return PKT_ERR_NODISC; /* No media */

   174     return gdrom_disc->read_sectors( gdrom_disc, sector, sector_count, mode, buf, length );

   175 }

   176 

   177 

   178 void gdrom_dump_disc_info( gdrom_disc_t disc ) {

   179     int i;

   180     int last_session = disc->track[disc->track_count-1].session;

   181     gboolean is_bootable = FALSE;

   182 

   183     INFO( "Disc ID: %s, %d tracks in %d sessions", disc->mcn, disc->track_count, 

   184 	  disc->track[disc->track_count-1].session + 1 );

   185     if( last_session > 0 ) {

   186 	/* Boot track is the first data track of the last session, provided that it 

   187 	 * cannot be a single-session disc.

   188 	 */

   189 	int boot_track = -1;

   190 	for( i=disc->track_count-1; i>=0 && disc->track[i].session == last_session; i-- ) {

   191 	    if( disc->track[i].flags & TRACK_DATA ) {

   192 		boot_track = i;

   193 	    }

   194 	}

   195 	if( boot_track != -1 ) {

   196 	    char boot_sector[2048];

   197 	    uint32_t length = sizeof(boot_sector);

   198 	    if( disc->read_sectors( disc, disc->track[boot_track].lba, 1, GDROM_MODE1,

   199 				    boot_sector, &length ) == PKT_ERR_OK ) {

   200 		bootstrap_dump(boot_sector, FALSE);

   201 		is_bootable = TRUE;

   202 	    }

   203 	}

   204     }

   205     if( !is_bootable )

   206 	WARN( "Disc does not appear to be bootable" );

   207 }

   208 

   209 gdrom_error_t gdrom_get_toc( char *buf ) 

   210 {

   211     struct gdrom_toc *toc = (struct gdrom_toc *)buf;

   212     int i;

   213 

   214     if( gdrom_disc == NULL )

   215 	return PKT_ERR_NODISC;

   216 

   217     for( i=0; i<gdrom_disc->track_count; i++ ) {

   218 	toc->track[i] = htonl( gdrom_disc->track[i].lba ) | gdrom_disc->track[i].flags;

   219     }

   220     toc->first = 0x0100 | gdrom_disc->track[0].flags;

   221     toc->last = (gdrom_disc->track_count<<8) | gdrom_disc->track[i-1].flags;

   222     toc->leadout = htonl(gdrom_disc->track[i-1].lba + gdrom_disc->track[i-1].sector_count) |

   223 	gdrom_disc->track[i-1].flags;

   224     for( ;i<99; i++ )

   225 	toc->track[i] = 0xFFFFFFFF;

   226     return PKT_ERR_OK;

   227 }

   228 

   229 gdrom_error_t gdrom_get_info( char *buf, int session )

   230 {

   231     if( gdrom_disc == NULL )

   232 	return PKT_ERR_NODISC;

   233     struct gdrom_track *last_track = &gdrom_disc->track[gdrom_disc->track_count-1];

   234     unsigned int end_of_disc = last_track->lba + last_track->sector_count;

   235     int i;

   236     buf[0] = 0x01; /* Disc status? */

   237     buf[1] = 0;

   238 

   239     if( session == 0 ) {

   240 	buf[2] = last_track->session+1; /* last session */

   241 	buf[3] = (end_of_disc >> 16) & 0xFF;

   242 	buf[4] = (end_of_disc >> 8) & 0xFF;

   243 	buf[5] = end_of_disc & 0xFF;

   244 	return PKT_ERR_OK;

   245     } else {

   246 	session--;

   247 	for( i=0; i<gdrom_disc->track_count; i++ ) {

   248 	    if( gdrom_disc->track[i].session == session ) {

   249 		buf[2] = i+1; /* first track of session */

   250 		buf[3] = (gdrom_disc->track[i].lba >> 16) & 0xFF;

   251 		buf[4] = (gdrom_disc->track[i].lba >> 8) & 0xFF;

   252 		buf[5] = gdrom_disc->track[i].lba & 0xFF;

   253 		return PKT_ERR_OK;

   254 	    }

   255 	}

   256 	return PKT_ERR_BADFIELD; /* No such session */

   257     }

   258 	

   259 }

   260 

   261 void gdrom_mount_disc( gdrom_disc_t disc ) 

   262 {

   263     gdrom_unmount_disc();

   264     gdrom_disc = disc;

   265     idereg.disc = disc->disc_type | IDE_DISC_READY;

   266     gdrom_dump_disc_info( disc );

   267 }

   268 

   269 gdrom_disc_t gdrom_mount_image( const gchar *filename )

   270 {

   271     gdrom_disc_t disc = gdrom_image_open(filename);

   272     if( disc != NULL )

   273 	gdrom_mount_disc( disc );

   274     return disc;

   275 }

   276 

   277 void gdrom_unmount_disc( ) 

   278 {

   279     if( gdrom_disc != NULL ) {

   280 	gdrom_disc->close(gdrom_disc);

   281     }

   282     gdrom_disc = NULL;

   283     idereg.disc = IDE_DISC_NONE;

   284 }

   285 

   286 gboolean gdrom_is_mounted( void ) 

   287 {

   288     return gdrom_disc != NULL;

   289 }
.